1) Field of the Invention
The present invention relates to a fluid filtering system, and more particularly, to a permanent fluid filtering system in which a filter layer can be effectively refined by pressurized air and clean fluid that are reversely fed into the system in a state where a filter layer is varied.
2) Description of Related Arts
Generally, a micro fluid filtering system is used, in a filtration plant, for pre-treating dirty and polluted fluid by filtering suspended solids contained in the fluid before the fluid goes to next highly processing steps (active carbonate, ozone, photocatalyst, and/or membrane separation processes).
The micro fluid filtering system has a filter provided with a fixed porous structure. This fixed porous structure makes it difficult or impossible to reversely refine the filter when the fixed porous structure is obstructed by dirty residue after being used for predetermined hours. Therefore, the filter must be replaced.
That is, since the porous structure is not changed during the reverse refining process of the system using pressurized air and clean fluid, the dirty residue obstructed in the porous structure is not easily removed, thereby reducing the reverse washing rate.